Backrest for a chair



FIG. 1 is an upper perspective view of the backrest for a chair;

FIG. 2 is a lower perspective view of the design shown in FIG. 1;

FIG. 3 is a front plan view of the design shown in FIG. 1;

FIG. 4 is a back plan view of the design shown in FIG. 1;

FIG. 5 is a left side plan view of the design shown in FIG. 1;

FIG. 6 is a right side plan view of the design shown in FIG. 1;

FIG. 7 is a top plan view of the design shown in FIG. 1; and,

FIG. 8 is a bottom plan view of the design shown in FIG. 1.

The broken lines shown in the drawings are for the purpose ofillustrating environmental subject matter and form no part of theclaimed design. The shade lines shown represent surface shading and notsurface ornamentation, color, or material type.

CLAIM I claim the ornamental design for a backrest for a chair, as shownand described.